Python for Loop

Sometimes a programmer wants to execute a group of statements a certain number of times. This can be done using loops. Based on this loops are further classified into following types; for loop, while loop, nested loops.

 

for Loop

for loops can iterate over a sequence of iterable objects in python. Iterating over a sequence is nothing but iterating over strings, lists, tuples, sets and dictionaries.

 

Example: iterating over a string:

name = 'Maxon'
for i in name:
    print(i, end=", ")

Output:

M, a, x, o, n,

 

Example: iterating over a tuple:

colors = ("Red", "Green", "Blue", "Yellow")
for x in colors:
    print(x)

Output:

Red
Green
Blue
Yellow

 

Similarly, we can use loops for lists, sets and dictionaries.

 

 

What if we do not want to iterate over a sequence? What if we want to use for loop for a specific number of times?

Here, we can use the range() function.

Example:

for k in range(5):
    print(k)

Output:

0
1
2
3
4

Here, we can see that the loop starts from 0 by default and increments at each iteration.

 

But we can also loop over a specific range.

Example:

for k in range(4,9):
    print(k)

Output:

4
5
6
7
8